1. Field of the Invention
The present invention relates to a structure for preventing surge of a 2-cylinder engine. More particularly, the present invention relates to a structure for preventing surge of a 2-cylinder engine which may prevent sharp pressure rising and descending within a crank room when 2 pistons of the engine moves up and down simultaneously and surge generated in an intake manifold.
2. Description of Related Art
In a general 2-cylinder engine, a first and a second piston are simultaneously and reciprocally moved for balancing in cranking.
That is, when a first cylinder is operated sequentially from intake stroke (piston descending), compression stroke (piston rising), explosion stroke (piston descending) and exhaust stroke (piston rising), a second cylinder is operated sequentially from explosion stroke (piston descending), exhaust stroke (piston rising), intake stroke (piston descending) and compress stroke (piston rising).
And thus, since two pistons of the 2-cylinder engine moves to the same direction simultaneously, so that when the pistons descend, pressure within a crank room is rapidly increased and negative pressure is created when the pistons rise.
Also, as shown in FIG. 1, the first cylinder and the second cylinder forms 1 cycle intake stroke during a 720 degree interval. From about 240 degree to about 480 degree, it is a deactivation of an intake valve and at this moment air compressed by a turbocharger is accumulated in the intake manifold.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.